Heart valves, such as the aortic valve, are sometimes damaged by disease or by aging, which can cause problems with the proper function of the valve. Heart valve problems generally take one of two forms: stenosis, in which a valve does not open completely or the opening is too small, resulting in restricted blood flow; or insufficiency, in which blood leaks backward across the valve that should be closed. Valve replacement may be required in severe cases to restore cardiac function.
Valve replacement can be performed through open-heart surgery, open chest surgery, or percutaneously. The native valve is removed and replaced with a prosthetic valve, or a prosthetic valve is placed over the native valve. The open chest and percutaneous procedures avoid opening the heart and cardiopulmonary bypass. Regardless of the procedure used, perivascular leakage can occur around the prosthetic valve and cannot be detected until the heart is closed and beating.
FIG. 1 shows a prosthetic aortic valve implanted in the aorta. Perivascular leakage, i.e., back flow from the ascending aorta 20 to the left ventricle 22 during diastole, will occur if the prosthetic aortic valve 24 is not sealed in the aorta, creating a perivascular leak 26. Some perivascular leakage may heal shut over time, but the healing is uncertain and the leakage reduces valve function until the healing is complete. Currently, repair of perivascular leakage requires an open-heart surgery to repair the leak with additional sutures. Repair may also require replacement of the prosthetic valve if the prosthetic valve size is incorrect. Open-heart surgery involves risk, expense, and an extended recovery time. Open-heart surgery also requires cardiopulmonary bypass with risk of thrombosis, stroke, and myocardial infarction.
It would be desirable to have a perivascular leak repair system that would overcome the above disadvantages.